Mechanical calculator.



Patented Apr. I5, I902.

no. 697,86l.

. w. H. MAcDOLLIN.

MECHANICAL CALCULATOR.

(Application filed Jan. 7, 1902.) (No Model.) 2 Sheets-Sheet l.

5 brim-- THE uonqls PETER; cc. PHDYO-LIYHOV, WASHINGTON, mc

=Nn. 697,86l. Patented Apr. l5, I902.

-W. H. MAGCULLINQ MECHANICAL CALCULATOR.

(Application filed Jim. 7, 1902.} (No Model.) 2 Sheets-Sheet 2.

me mums FEYERS w, worutvrnou WASHINGTON. n. cy

NrTnD STATES: ATENT OFFICE.

\VILLIAM H. MAOOOLLIN, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE lVARREN-EHRET COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

MECHANICAL CALCULATOR.

SPECIFICATION forming part of Letters Patent No. 697,861, dated April 15, 1902. Application filed January 7 1902. Serial No. 88,771. (No model.)

T l wh it y Concern: O, upon either side of which a row of spaces 0 Be it known that I, WILLIAM H. MAOOOL- is placed, containing a series of numbers, said LIN, a citizen of the United States, residing pointer having at its end opposite the pivot in Philadelphia,Pennsylvania,haveinvented a point I). The dial and pointer are con- 5 certain Improvements in Mechanical Oalcunected together, so as to be movable with relators or Scales, of which the following is a lation to each other, and either may be fixed, specification. as may be most desirable to the user. The

My invention relates to a device for perpointer is secured to the dial ordisk by means forming calculations mechanically. It has of a tubular rivet d, and in order that the :0 been devised particularly for use by archimovement of either of these parts with relatects for the purpose of calculating the numtion to the other may not cause appreciable her of steps of definite height or riser between wear the dial or disk is provided with a tubufioors of houses and other buildings when the lar rivet c, forminga bearing for and withspace between such floor is known. in which the rivet d, holding the pointer, is I 5 My invention further includes an addi placed.

tional scale for use in connection with the The figures on the concentric lines (1 and e riser-scale to indicate the treads for are to indicate the height of the houses or such risers. other buildings between floors. The figures My invention is fully illustrated in the acin the spaces a indicate in inches the possi- 2o companying drawings, in which- 1 ble height of the stair-risers, while the figures Figure l is an elevation or face View of the on the pointer or arm indicate the number of structure forming the subject of my invensteps which may have risers of different tion, showing the dial or disk containing the heights between floor-spaces of known height. series of predetermined dimensions and the In general practice it may be noted that 25 pointer used in connection with the same. stair-risers range from six to eight inches.

Fig. 2 is a sectional view of the structure Only inrare instances are dimensions greater shown in Fig. 1, taken on the line 00' m. Fig. or less than these employed, and hence my 3 is an elevation or face view of a portion of improved scale has been devised for use bea dial or disk and a duplex pointer, illustrattween these extremes of height for the stair- 30 ing a modification of my invention; and Fig. riser. It will be understood, however, that 4 is an edge view, partly in section, of a dial other dimensions may be provided for by or disk with a duplex pointer, illustrating multiplying the dimensions-to be foundupon 1 another modification of my invention. the scale or by adding other groups of fig- IntheaccompanyingdraWings,Arepresents ures thereto on either side of those found on 3 5 a dial or disk having a number of spaces a the disk in regular ascending or descending formed by concentric lines I) and radial lines progrcssion,which may be readily determined ,0, each of which has a common center a. from the other dimensions.

Within certain of the spaces a formed by the The disk or dial shown in Fig. 1 is provided concentric and radial lines figures are writwith two sets of numbers within the spaces 40 ten representing stair-riser dimensions in a, and dividing these sets of numbers is the inches and fractions of an'inch. Exterior to heavy radial line D. To the right of this the series of concentric lines I) are the lines line the numbers in the small spaces are to d and e, the latter being divided into'equal be read in connection with the numbers on spaces representing feet, while the former the pointer at the left of the slot in the same, 5 are divided into equal spaces representing while the numbers in the spaces to the left inches. y of the line D are to be read in connection 5 Pivotally mounted at the center a of the with the numbers carried by the pointer at dial or diskAand free to rotate with relation the right-hand side of its slot. thereto is the pointer or arm B, having a slot The scale is employed in the following manner: Suppose, for instance, a house or other building under construction is to have floors nine feet apart. To find the number of steps or stairs and the height of the risers of the same, we turn the pointer of the scale until its outer end 1) lies directly over the figure 9 in the outer concentric circles. Reading then the dimensions showing through the slot in the pointer in connection with the numbers carried by the pointer to the left of the slot, we find that in the nine-foot space between the floors eighteen steps can be laid with six-inch risers, fifteen steps with seven and one-fifth inch risers, or fourteen steps with seven and five-sevenths inch risers, and so on. If the space between the floors is nine feet six inches, the pointer is moved to the six-inch mark beyond the nine-foot mark and the numbers read as before, and so on throughout the scale. IVhen it is desired to divide a floor of greater heightsay, for instance, fifteen feet nine inches-the dimensions in the spaces a to the left of the line D will be read in connection with the figures on the right-hand side of the pointer. For this dimension there may be thirty-one steps having six and three thirty-firsts inch risers, thirty steps with six and three-tenths inch risers, and so 011 up to twenty-four steps with seven and seven-eighths inch risers. In architectural practice a certain rule is followed with regard to the relation of a stair-riser with the tread, and this relation is such that the multiplication of the one by the other should equal or nearly equal, but never exceed, seventy-five square inches.

My improved scale as arranged and as shown in Fig. 1 is designed solely to denote the stair-riser. I may provide with it, however, an additional scale to be above or below the scale indicated by the dimensions in the spaces a. For instance, in Fig. 3 I have shown an additional scale for stairtreads arranged within the riser-scale, or I may provide two pointers firmly secured together at their pivotal point by suitable means passing through an aperture at the center of the dial or disk, as clearly shown in Fig. 4:, and on each face of such dial or disk show a series of dimensions registering with each other, the set of such dimensions on one side representing the risers, while the set on the other side represents the tread of the step.

In Fig. 3 I have shown a view of a dial or disk A having on one face the dimensions for both risers and treads, the latter being arranged near the center of the disk. With this form of scale a single pointer B is employed, having two slots 0 and 0, both of which have the same figures disposed at either side.

In Fig. LI have shown an edge view, partly in section, indicating a form of scale comprising a dial or disk with a pointer or arm 13*, comprising a continuous member, which is bent so that it may be disposed on each face of the dial or disk, and the free ends of this pointer have a pivotal connection similar to the other pointers.

Although I have shown and described my scale as one having dimensions arranged in concentric rows, I do not wish to be limited to such form of structure, as I may employ a square or rectangular chart, with a pointer arranged to move at right angles to the same, such form of structure having marks and dimensions similar in all respects to the disk or dial scale.

By the use of a scale of the character devised by me all trouble of plotting the necessary steps, together with the mathematical calculations involved, is dispensed with and a great saving of valuable time effected.

Having thus described my invention, I claim and desire to secure by Letters Patent- 1. A calculating device comprising a chart of suitable form having a series of spaces, certain dimensions marked within said spaces, lines adjacent to, but beyond the spaces containing the dimensions, such lines being divided into parts of equal length, a divisionline for the dimensions marked within the spaces of the chart, the said dimensions differing in character on either side of said division-line, and a pointer suitably mounted with relation to the chart, one of said members being movable With respect to the other, said pointer having an opening equal to one row of spaces and having also a series of numbers disposed on either side of said slot, which numbers are to be read when the end of the pointer is opposite one of the markings of the outer lines, in connection with the numbers viewed through said opening, the numbers on one side of said slot being read in connection with the dimensions on one side of the dividing-line, and vice versa.

2. A calculating device consisting of a disk having a series of spaces formed by radial and concentric lines having a common center, certain dimensions marked in said spaces, outer concentric circles divided into a series of spaces of equal length, a division-line for the dimensions marked within the spaces of the disk, the said dimensions differing in character on either side of said division-line, and a pointer mounted at the center of the dial or disk, one of said members being movable with respect to the other, said pointer having a slot overlying the series of dimensions marked within the concentric spaces, and having also a series of numbers disposed 011 either side of said slot, which numbers are to be read, when the end of the pointer is opposite one of the markings of the outer circle, in connection with the numbers viewed through said slot, the numbers on the left-hand side of said slot being read in connection with the dimensions 1 o 3. A calculating device having a series of same is brought opposite one of the marks inspaces With dimensions therein representing dicating the height between floors. stair-risers, another series of spaces with In testimony whereof I have signed my dimensions therein representing stairname to this specification in the presence of 5 treads, marks arranged beyond said spaces two subscribing witnesses.

to indicate heights between floors, and a slotted pointer carrying certain figures indicatv MACOOLLIN' ing the number of steps, the dimensions of \Vitnesses: risers and treads being viewed through MURRAY 0. BOYER,

10 the slot of the pointer when the end of the Jos. H. KLEIN. 

